Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

There are no annotations, so the description carries the behavioral burden. It does disclose a meaningful trait ('Page content is not stored'), which adds value beyond the schema. However, it does not address network behavior, errors, redirects, or what happens with invalid URLs.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two short sentences with no wasted words. The main function is front-loaded and the non-storage guarantee is a separate, valuable behavioral note.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema and no annotations, a seven-property input schema needs more contextual support in the description. The description only explains the URL behavior and leaves ref, city, feed, host, json, and path unexplained, making it unclear whether these are alternate modes or incidental parameters.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

All seven parameters have descriptions in the input schema, so the 100% coverage baseline applies. The description does not add per-property detail, but it does tie the URL parameter to the expected outputs (host, scheme, HTTP status), which is modest additional meaning.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description uses a specific verb ('Return') and names the resource ('URL') plus the exact outputs (host, scheme, HTTP status). It is clearly not a generic statement, but it does not distinguish itself from siblings like fetch-status, normalize-url, or web-fetch.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is given about when to use this tool versus alternatives such as normalize-url, fetch-status, or web-fetch. The phrase 'Page content is not stored' provides an implicit privacy context, but there is no explicit when-to-use or when-not-to-use direction.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.